This invention relates to a frequency multiplier device, and more particularly to a frequency multiplier device using a semiconductor element to multiply a frequency of an alternating current signal.
Conventional semiconductor frequency multiplier devices have used the semiconductor device including only a pair of electrodes or terminals and typically the semiconductor diode called "VARACTOR" (trade mark) to use in parametric amplification. Such a diode includes a single pair of electrodes or terminals disposed on a pair of main opposite faces of its semiconductive body including a p-n junction and has a nonlinear electric field-to-current characteristic developed between that pair of electrodes or terminals. The nonlinear electric field-to-current characteristic as it stands has been utilized to multiply a frequency of an alternating current (ac) signal applied to the diode. More specifically, an ac signal has been applied across the electrodes on the diode to form an output signal including different harmonic components. Then by using a special filter, only that harmonic component multiplied in frequency as desired has been taken out from the output signal. In such conventional devices, the output signal has been developed across the same electrodes across which input signal has been applied. In other words, the pair of electrodes have been necessarily used not only to supply the input signal thereacross but also to take out the output signal therefrom. Thus it has been difficult to separate the output signal from the input signal and therefore to use such conventional frequency multiplier devices. In addition, the conventional devices have been required to be operatively associated with a special filter or filters in order to take out a desired harmonic component from the output signal resulting in the complication of the constructions thereof.
Accordingly it is an object of the present invention to provide a new and improved semiconductor frequency multiplier device for easily separating an output signal from a corresponding input signal applied thereto with a simple construction.